An air filter designed to remove particulate is generally a device composed of fibrous materials. These fibrous materials may remove solid particulates such as dust, pollen, mold, and bacteria from the air. Air filters are used in applications where air quality is important, notably in building ventilation systems and in automobile engines.
Air filters may be used in automobiles, trucks, tractors, locomotives and other vehicles that use internal combustion engines. Air filters may be used with gasoline engines, diesel engines, or other engines that run on fossil fuels or other combustible substances. Air filters may be used with engines in which combustion is intermittent, such as four-stroke and two-stroke piston engines, as well as other types of engines that take in air so as to burn a combustible substance. For example, air filters may be used with some gas turbines. Filters may also be used with air compressors or in other devices that take in air.
Filters may be made from pleated paper, foam, cotton, spun fiberglass, or other known filter materials. Generally, the air intakes of internal combustion engines and compressors tend to use paper, foam, or cotton filters. Some filters use an oil bath. Air filters for internal combustion engines prevents abrasive particulate matter from entering the engine's cylinders, where it would cause mechanical wear and oil contamination. Many fuel injected engines utilize a flat panel pleated paper filter element. This filter is usually placed inside an enclosed, plastic box connected to a throttle body by way of ductwork. Vehicles that use carburetors or throttle body fuel injection systems typically use a cylindrical air filter positioned above the carburetor or the throttle body.
A drawback to enclosed air boxes that require flat panel paper filters is that air flow through the filter becomes restricted as particular matter builds up in the filter. Such a restricted air flow generally leads to a reduction in engine performance, such as a decrease in engine power output and greater fuel consumption. Moreover, as the paper filter becomes increasingly clogged, pressure inside the filter decreases while the atmospheric air pressure outside the filter remains the same. When the difference in pressure becomes too great, contaminants may be drawn through the paper filter directly into the engine. Thus, the ability of the paper filter to protect the engine from contamination and internal damage tends to decrease near the end of the filter's service life. Typically, paper air filters are removed from the vehicle and discarded, and a new paper air filter is then installed. Considering that there are millions of vehicles throughout the world, the volume of discarded air filters that could be eliminated from landfills is a staggering number. Another drawback to enclosed air boxes is that they typically draw air through a tortuous path of hoses or ductwork before the air enters the intake of the engine. In some cases, the air box is a greater source of air restriction than is the paper filter. Similar to a contaminated air filter, a restrictive air box decreases engine performance and fuel economy.
FIG. 1 illustrates an exemplary embodiment 100 of an air box 104 with an integrated air filter 108 which solves the above-mentioned drawbacks to conventional air filters. The air box 104 comprises a housing portion 112 and a mount portion 116. The air box 104 generally is comprised of a material which is sufficiently durable and temperature resistant to retain its configuration during installation and operation when coupled with the air intake system of an automobile. The air box 104 generally is of an open variety, thereby improving airflow to the air filter 108, and thus improving engine performance beyond that otherwise possible with an enclosed air box. The mount portion 116 generally is configured to be mounted, or fastened, to the interior of an automobile engine bay.
The housing portion 112 generally is configured to support the air filter 108 and provide an interface between the air filter 108 and an intake portion of an automobile engine. A front side of the housing portion 112 comprises a conduit 120 that is configured to receive an air intake conduit extending to the intake portion of the automobile engine. Typically, a longitudinal dimension of the conduit 120 is positioned at an angle relative to the housing portion 112. Generally, the value of the angle between the conduit 120 and the housing portion 112 depends upon the particular automobile for which the air box 104 is to be utilized. Further, the conduit 120 comprises a flange 128 and an opening 132. The opening 132 serves the function of conducting air drawn through the air filter 108 into an interior cavity 136 of the filter into the air intake of the automobile engine. The specific configuration of the flange 128 and a diameter of the opening 132 generally depend upon the particular make and model of the engine for which the air box 104 is to be utilized.
With continuing reference to FIG. 1, the air filter 108 comprises a filter material 156 and a distal end cap 164. The distal end cap 164 may be affixed to the filter material 156 by way of any of a variety of fasteners (not shown), or may be molded to of the air filter 108. The distal end cap 164 typically is comprised of a material which is sufficiently hard so as to retain the filter material 152 in the desired configuration and support the air filter 108 when coupled to the housing portion 112. As shown in FIG. 1, the filter material 156 circumferentially surrounds the interior cavity 136 such that the filter material 156 creates an exterior perimeter of at least a portion of the interior cavity 136. The filter material 156 generally provides a surface area through which to pass an air stream and trap particulate matter and other contaminates so as to prevent them from entering into the air intake of the automobile engine.
It will be appreciated that a user of the air box 104 may periodically clean the air filter 108 rather than replacing the air filter, as is typically done with conventional air filter systems. A straightforward method for cleaning the air filter 108 comprises removing the air intake conduit of the automobile engine from the conduit 120, inserting a water hose through the opening 132 into the interior cavity 136 of the filter, and spraying water so as to flush contaminants from the filter material 156. A drawback to this cleaning method is that the user must attempt to bend the hose inside the interior cavity 136 so as to direct the water stream onto the filter material 156. Bending the hose within a small area, such as the interior cavity 136, often causes the hose to crimp, thereby reducing water flow and consequently hindering effectively cleaning the air filter 108.
Another drawback to bending the hose within the interior cavity 136 is that generally the user will not be able to uniformly clean the filter material 156. In an attempt to avoid crimping the hose, the user may consider using a water nozzle which directs the water stream at an angle relative to a longitudinal axis of the hose. However, typically available water nozzles, such as garden-variety nozzles, are often too big to fit through the opening 132 of the conduit 120 and into the interior cavity 136. Moreover, many garden-variety water nozzles have sharp edges and bulky features which may damage or even puncture the filter material 156, thereby ruining the air filter 108. What is needed, therefore, is an air filter cleaning device to flush contaminants from an intake air filter of an automobile engine without damaging the air filter material.